System: A system is made of parts with relationships creating one or more feedback loops with circular causality so that the characteristics of the whole are not characteristics of any of the parts.

System Dynamics is the practice of understanding general policies, rather than guiding particular decisions, by comparing mental models with a visual model where each assumption, part and relationship is defined and the behavior resulting from dynamic simulation is communicated.

System Dynamics requires defining people's current paradigm, their present mind-set, what is the goal of your system, what is the overall structure so that we can see assumptions and feedback loops.

Systems Thinking is the qualitative presentation of results from a dynamic model simulation using computer modeling.

Mental Model is a person’s conceptual understanding of the behaviors relevant to a specific system.